1. Field of the Invention
The present invention relates to tape dispensers and, more specifically, to a tape dispenser having printing means for printing the tape being dispensed.
2. Description of the Related Art
U.S. Pat. Nos. 5,947,025 and 6,112,659 respectively disclose a tape dispenser capable of printing patterns and words on the tape dispensed thereby and an adhesive tape dispenser provided with means for printing adhesive tape being dispensed. When the adhesive tape applied to the carton or the like, it seals the carton and, simultaneously provides a marking or advertising effect. The sprinting wheels of the aforesaid two U.S. patents (the member referenced by 30 in U.S. Pat. No. 5,947,025 and the member referenced by 40 in U.S. Pat. No. 6,112,659) are, as shown in FIG. 1, commonly comprised of a hard wheel body A (generally molded from plastics) and a flexible printing plate B (generally made of rubber). The flexible printing plate B has patterns and words formed thereon and, is adhered to the periphery of the wheel body A. Alternatively a packing strip (not shown) may be used to fasten the ends of the flexible printing plate B to the periphery of the wheel body A.
These two printing wheel designs have numerous drawbacks as outlined hereinafter.
1. Because the flexible printing plate is adhered to the periphery of the wheel body or fastened thereto by a packing strip, it tends to be forced out of the wheel body.
2. The flexible printing plate may be not smoothly evenly covered on the periphery of the hard wheel body, resulting in poor printing quality.
3. Due to technique limitations, sufficient space must be left in the four sides of the top surface of the rectangular flexible printing plate around the patterns and words during formation of the patterns and words. When the flexible printing plate rolled up into a roll around the periphery of the wheel body, a big blank area is left around the abutted ends of the flexible printing plate. The installation of the packing strip also requires a big blank area around the abutted ends of the flexible printing plate. When continuously circulating the printing on the adhesive tape being dispensed, an interrupted blank area appears on the adhesive tape being dispensed at every unit distance (the packing strip may produce an ink trace on the adhesive tape being dispensed). On the other words, cannot print a continuous series of patterns and words without leaving a trace of the ends of the flexible printing plate.
4. Because the flexible printing plate is made of rubber, the printing surface of the patterns and words tends to be deformed when contacting the underside of the adhesive tape being dispensed, resulting in a vague printing quality. Due to the aforesaid drawbacks, the prior art designs are not suitable for printing fine patterns and fine words.
Further, the aforesaid two prior art designs commonly have an ink supplying device (commonly referenced by 50). According to these two U.S. patents, the ink supplying device comprises an ink storage cassette (referenced by 55 in U.S. Pat. No. 5,947,025, or 51 in U.S. Pat. No. 6,112,659), and a roller-like ink soaking member (referenced by 56 in U.S. Pat. No. 5,947,025, or 53 in U.S. Pat. No. 6,112,659) made of sponge and fastened rotatably with the ink storage cassette. The roller-like ink soaking member soaks up ink from the ink storage cassette, and keeps the periphery in close contact with the printing plate of the printing wheel. When the printing wheel rotated by the tape being dispensed, the roller-like ink soaking member is rotated to apply ink to the printing surface of the printing plate of the printing wheel, thereby causing the printing wheel to print patterns and words on the underside of the tape being dispensed.
The aforesaid ink supplying device is still not satisfactory in function. When the roller-like ink soaking member soaked up ink in the saturated status, excessive amount of ink may be applied to the periphery of the printing wheel, resulting in poor printing quality. Further, because the roller-like ink soaking member cannot keep ink wet for long, ink soaked up by the roller-like ink soaking member easily changes into vapor, resulting in unclear or thin printing on the tape being dispensed. In general, the use of the aforesaid ink supplying device makes printing quality control difficult.
The present invention has been accomplished to provide a tape dispenser having printing means for printing the tape being dispensed, which applies ink to the printing surface of the printing wheel evenly to achieve a high quality printing effect.
It is another object of the present invention to provide a tape dispenser having printing means for printing the tape being dispensed, which keeps ink from changing into vapor quickly.
It is still another object of the present invention to provide a tape dispenser having printing means for printing the tape being dispensed, which is durable in use and, achieves a high printing quality.
To achieve these objects of the present invention, the tape dispenser comprises a main body; a tape roll holder mounted on the main body to hold a tape roll such that the tape roll can be turned; a tape cutter mounted on the main body; a printing wheel fastened pivotally with the main body; an ink supply unit located on the main body, the ink supplying unit comprising an ink supply device adapted to apply ink to the periphery of the printing wheel. The printing wheel comprises a printing wheel body formed in integrity of hard material. The printing wheel body has a cylindrical base, and a plurality of protruded portions raised from the periphery of the cylindrical base and forming a printing surface around the periphery of the cylindrical base. The printing surface is coaxial to the cylindrical base. The ink supplying device comprises a housing detachably mounted on the main body for receiving ink therein, a porous ink soaking layer mounted inside the housing and adapted to soak the ink, and a fabric ink applying layer covered on the porous ink soaking layer and partially exposed to the outside of the housing. The fabric ink applying layer is disposed in contact with the periphery of the printing wheel at one side when the ink supplying device installed in the main body.
The printing wheel is made by using a programmable engraving machine to engrave a hard cylindrical base material into the desired finished product subject to a predetermined design. Because the printing surface is formed integral with the hard cylindrical base material, the printing surface does not drop from the printing wheel body. Because the protruded portions (printing surface) of the printing wheel body are a part of the circumference of the cylindrical base material before engraving, the finally finished printing surface has a good roundness that can be closely attached to the underside of the adhesive tape being dispensed to achieve a high quality printing. Because the printing wheel is made of hard material (for example, aluminum), the printing surface does not deform during printing, and fine patterns of the design of the printing surface can be clearly printed on the adhesive tape being dispensed. Further, because the printing surface is formed integral with in the periphery of printing wheel, the design of the printing surface has no interruption in it.